When a display device performs displaying, a nonlinear relationship is present between the input voltage applied to a pixel and the pixel brightness/transmittance. The curve reflecting such a nonlinear relationship is referred to as the Gamma curve.
The existing display device when being used all need to perform voltage conversion based on a preset Gamma characteristic curve. The difference between the Gamma value of the actual Gamma characteristic curve of the display apparatus and a target Gamma value (usually 2.2) determines the final display effect. The smaller the difference is, the better the display effect is.
Therefore, before display apparatuses are actually sold to customers/users, it is needed to perform some tests on the display apparatuses to obtain a Gamma curve whose Gamma value is as close to the target Gamma value as possible.
In the prior art, for a certain gray scale, an initial voltage is first output, and then the pixel brightness is tested to determine whether they have a power exponent relationship with a base of 2.2. If not, the initial voltage is adjusted and then the pixel brightness is tested to determine whether they have a power exponent relationship with a base of 2.2. The above procedure is repeated until the final voltage corresponding to the gray scale is found and a Gamma curve is created based on the brightness corresponding to the voltage.
It can be found that the above procedure for determining the Gamma curve is very cumbersome, and has low efficiency.